Aircraft safety is an ongoing concern for aircraft producers. An unknown loose object on board an aircraft may cause an aircraft to malfunction or not operate as designed. Unknown loose objects are referred to as foreign object debris (FOD) in the art.
FOD are difficult to detect and many hours of searching an aircraft for FOD occur during production of an aircraft, to assure the aircraft is free from loose objects, before the aircraft leaves a production facility or is operated. Moreover, because the detection of FOD relies almost solely on visual inspection, it can be subject to human error.
FOD are of various size and shape and can go undetected in large aircraft. A large aircraft has various cavities, pockets, and crevices that cause the process of detecting FOD to be difficult. For example, a small FOD item, such as a metal shaving or drill bit, lying in a dark crevice may go undetected during the search of a large aircraft. These metal shavings and drill bits may cause damage to wires and tubing. As one of ordinary skill thus appreciates, the more the amount of undetected FOD, the more the likelihood exists of an aircraft system malfunctioning.
A current method exists for locating a component that requires a supplemental restraining device on a portion of a gas turbine engine, as described in Garrity U.S. Pat. No. 6,150,656 entitled “Method of Assembly and Inspection for a Gas Turbine Engine”, hereinafter referred to as Garrity. In Garrity, a fluorescent material is applied to components of a gas turbine engine that require a supplemental restraining device before assembly thereof. An electromagnetic radiation is directed at the gas turbine engine to illuminate the fluorescent material. Upon illumination of the fluorescent material, a confirmation is made as to whether the components that requires a supplemental restraining device do in fact have a supplemental restraining device properly installed. As known in the art and as taught by Garrity, in order to properly install a supplemental restraining device, such as a lock-wire, to a component, the component must be fixed otherwise the supplemental restraining device does not serve its intended purpose.
One known method of detecting foreign object debris is described in Wagoner et al., U.S. Patent Application entitled “A Method for Detecting Foreign Object Debris”, hereinafter referred to as Wagoner. Wagoner teaches a method of detecting a non-fixed object, such as a fastener, within an aircraft. A light emitting substance is applied to the non-fixed object. A non-fixed object illuminator is used to illuminate the light emitting substance. The non-fixed object is detected due to the illumination of the light emitting substance.
In both Wagner and Garrity above, the light emitting substance is directly applied to the non-fixed object prior to any manufacturing or assembly steps. However, FOD is also created during the manufacturing and assembly of aircraft. For example, FOD in the form of metal shavings is created during hole drilling operations. These metal shavings could be a portion of the drilled substrate or could be portions of the deteriorating drill bits. Drill bits and metal shavings are hard to detect and can be sharp, potentially causing damage to wires and tubings.
Thus, it is highly desirable to easily detect and remove FOD created during hole drilling operations.